A passive entry
system, in particular for a motor vehicle, comprising: a
mobile device to be carried by a user, said
mobile device comprising a low-frequency
transceiver for short range communication, an ultra-high-frequency
transceiver for long range communication and information concerning access, such as an access code, which is transmittable by said transceivers; and a locking device which is to be unlocked by the
mobile device, said locking device comprising a low-frequency
transceiver for short-range communication and an ultra-
high frequency transceiver for long range communication to receive said information concerning access, such the access code. The transceivers of the mobile device communicates with the transceiver of the locking device and exchange information concerning access, such as said access code, to the locking
system via the respective transceivers, wherein the communication range of the ultra-high-frequency transceiver of the mobile device is limited to a short range in a normal operating mode of the mobile device.